Household size is on a long term negative trend due to fewer children and later marriage, as well as longer lifespans. My grama for example lives alone in a 2200SF house that used to have 4 residents. And when she was 24 she was in a household with a husband and 2 children. How many 24 year old women in California can say that?
Aside from changes in family trends, the good economy is splitting up roommates households and boomerang children situations.
These are trends that are, overall, good for the market. But some of these new households are starting in the suburbs, leaving a smaller household behind in San Diego.
